1. Field of the Invention
The present invention relates to a modem and a method of processing data, and more particularly to a modem installed between a subscriber terminal and a switching system, for processing a received data packet.
The present application is based on Korean Patent Application No. 2000-45738, filed Aug. 7, 2000, which is incorporated herein by reference.
2. Description of the Related Art
Various related art network communication service technologies are available to general users for providing high-speed communication services. Among the related art technologies, an Asymmetric Digital Subscriber Line (ADSL) is widely used due to a high-speed data transmission via existing telephone lines. The related art ADSL service provides a maximum 8 Mbps downstream rate and a maximum 1 Mpbs upstream rate.
Major parts of the related art ADSL service system include a central service part (e.g., a central telephone office for managing telephone lines concentrated to the central service part), a subscriber service part, and a connecting part for connecting the central service part to a data backbone.
FIG. 1 is a block diagram showing a related art ATM switching system connected to a subscriber terminal through the ADSL modem in a general ADSL communication service system. The subscriber terminal 10 is connected to a Network Access Server (NAS) 40 through an ADSL Terminal Unit-Remote (ATU-R) 20, and a Digital Subscriber Line Access Multiplexer (DSLAM) 30.
The DSLAM 30 is the ATM switching system unit (i.e., the central service part), and includes an ADSL Terminal Unit-Center (ATU-C) and an ATM switch. The ATU-R 20 is the ADSL modem (i.e., the subscriber service part), connecting the DSLAM 30 and the subscriber terminal 10. The ATU-R 20 is generally called a Customer Premise Equipment (CPE).
The ATU-R 20 as a related art subscriber modem performs either in a router mode or a bridge mode which is recommended in a Request for Comments (RFC) 1483, for processing two-way data transmission/reception between the subscriber terminal 10 and a remote area network. The RFC is TCP/IP specification or service standard disclosed through a server on the Internet with an address of (http://ds.internic.net/) by the IETF (Internet Engineering Task Force), an Internet Research and Development Institute. Each RFC has a serial number assigned thereto for identification of the contents of the RFC.
The ATU-R 20 operating in the router mode processes received data with a support of an Internet Protocol (IP) module such that the IP module that supports a Transmission Control Protocol/Internet Protocol (TCP/IP) based service is layered on an execute protocol stack.
The ATU-R 20 operating in the bridge mode processes data at an interface between the subscriber terminal 10 and the DSLAM 30. The IP module is not layered on the execute protocol stack of the ATU-R 20 when operating in the bridge mode.
However, the related art ASDL service system has various problems and disadvantages. For example but not by way of limitation, as shown in FIG. 2, since the ATU-R 20 operating in the bridge mode does not have the IP module, status information of the ATU-R 20 (e.g., a data processing speed thereof) cannot be obtained by a user even though the user executes application programs (e.g., telnet and embedded web) installed in the subscriber terminal 10. While the status information of the related art ATU-R 20 operating in the bridge mode may be obtained through a RS-232 console or a special method supported by a Central Processing Unit (CPU) of the ATU-R 20, such related art methods require professional skills of an ATU-R developer. As a result, general users are unable to easily use the related art ASDL service system.